Downhole sealing device and method of making

ABSTRACT

Disclosed herein is a downhole sealing device. The device includes, a swellable member, and a passageway having a perimetrically continuous wall. The swellable member is configured to cause sealing between a downhole structure and a plurality of tubulars when in a swelled condition, the plurality of tubulars are routed through a plurality of voids extending longitudinally through the swellable member, each of the plurality of voids has perimetrically continuous walls surrounding each of the plurality of tubulars.

BACKGROUND

It is common in the hydrocarbon recovery industry to have a need to plugan annular space defined by a tubular and a downhole wellbore structure,such as, a liner, casing or open hole, for example, within which thetubular is positioned. One sealing method includes positioning aswellable member perimetrically about the tubular prior to positioningthe tubular within the downhole structure. The swellable member swellsin response to exposure to downhole fluids such as oil or water forexample. The swelling of the swellable member causes the swellablemember to fill the annular space and to sealingly engage with walls ofboth the tubular and the downhole structure.

Establishing and maintaining a well secured communication from one sideof the swellable seal to the other can be useful in well operations.Unsecured communication lines can have a far greater operational cost,which may result in having to exit from the borehole in order to makefurther securing repairs. Excessive vibration caused by one tooltraveling down the borehole may adversely affect the performance ofother tools obtaining valuable downhole data. That vibration creationalong with unsecure communication lines may only amplify false results.Such amplification from those unsecure lines would be in comparison to atuning fork when strike. In most gamma ray equipped downhole tools, thesmooth transition of multiple or single photo multiplier tubes areimportant in order to provide the necessary pulse of light via thetubes. Any sharp bends or vibration may only destroy this very importantlight communication. Another example is on a telemetry downhole tool,mud pulses are registered by these types of tools via an electricalsensor. Any additional impacts from unsecured communication lines willonly amplify noises or even provide false readings that are important tothis data gathering. Systems and methods, therefore, that permit sealingand maintaining a solid lock down in an annular space while maintaininga communication passageway across the seal are desirable in the art.

BRIEF DESCRIPTION

Disclosed herein is a downhole sealing device. The device includes, aswellable member, and a passageway having a perimetrically continuouswall. The swellable member is configured to cause sealing between adownhole structure and a plurality of tubulars when in a swelledcondition, the plurality of tubulars are routed through a plurality ofvoids extending longitudinally through the swellable member, each of theplurality of voids has perimetrically continuous walls surrounding eachof the plurality of tubulars.

Further disclosed herein is a downhole swellable sealing system withpassageway. The system includes, at least one substantially nonswellablemember, and a swellable member in operable communication with the atleast one substantially nonswellable member. The swellable member isconfigured to cause sealing between a downhole structure and a pluralityof tubulars when in a swelled condition, the plurality of tubulars arerouted through a plurality of voids that extend longitudinally throughat least one of the swellable member and the at least one substantiallynonswellable member, and each of the plurality of voids hasperimetrically continuous walls surrounding each of the plurality oftubulars.

Further disclosed herein is a method of making a downhole swellable sealwith a passageway therethrough. The method includes, perimetricallysurrounding a first tubular with a first substantially nonswellablematerial, perimetrically surrounding at least one second tubular with asecond substantially nonswellable material, positioning the at least onesecond tubular adjacent the first tubular, perimetrically surroundingthe first tubular and the at least one second tubular with a swellablematerial, curing the first substantially nonswellable material, curingthe second substantially nonswellable material, and curing the swellablematerial.

BRIEF DESCRIPTION OF THE DRAWINGS

The following descriptions should not be considered limiting in any way.With reference to the accompanying drawings, like elements are numberedalike:

FIG. 1 depicts a perspective view of a downhole swellable sealing systemwith passageway as disclosed herein;

FIG. 2 depicts a magnified side view of a portion of the downholeswellable sealing system of FIG. 1;

FIG. 3 depicts a cross sectional side view of an embodiment of theswellable sealing system of FIG. 2;

FIG. 4 depicts a perspective view of the swellable sealing system ofFIG. 1 during a forming operation of perimetrically continuous voids;and

FIG. 5 depicts a cross sectional side view of an alternate embodiment ofthe swellable sealing system of FIG. 2.

DETAILED DESCRIPTION

A detailed description of one or more embodiments of the disclosedapparatus and method are presented herein by way of exemplification andnot limitation with reference to the Figures.

Referring to FIGS. 1 and 2, an embodiment of the swellable sealingsystem 10 with passageway disclosed herein is illustrated. The swellablesealing system 10 includes, a substantially nonswellable member 18, aswellable member 22, and at least one void 28 with a perimetricallycontinuous wall extending longitudinally through at least one of thesubstantially nonswellable member 18 and the swellable member 22. Thesubstantially nonswellable member 18 perimetrically surrounds a firsttubular 14 and at least one second tubular 26 is positioned within thevoid 28. The second tubular 26 is preferably constructed of a rigidmaterial such as stainless steel, for example, and has an inner cavitydefining a passageway 30 (as best illustrated in the cross sectionedviews in FIGS. 3 and 5). The swellable sealing system 10 is configuredto seal an annular space 34 defined in this embodiment by the firsttubular 14 and a downhole structure 38 that the system 10 is positionedsubstantially concentric with, such as, a liner, casing or open hole,for example, while providing the passageway 30 therethrough, via thesecond tubular 26. It should be noted that alternate embodiments couldbe configured to seal an annular space that is defined radially inwardlyof the first tubular 14 and radially outwardly of a downhole structurepositionable within at least a portion of the first tubular. Thepassageway fluidically connects a portion of the annular space 34Abeyond one longitudinal end of the nonswellable member 18 to a portionof the annular space 34B beyond an opposite longitudinal end of thenonswellable member 18. The passageway 30 can be used as a control linedirectly with hydraulic fluid being ported therethrough, for example, oras a conduit for running a separate control line (not shown), such as,electric line or fiber optic cable, for example.

The swellable member 22 may be constructed of any swellable materialknown in the industry such as polymers that swell when exposed toconditions commonly encountered downhole such as oil or water, forexample. In contrast, the nonswellable member 18 may be constructed ofknown materials that tend to be substantially nonswellable when exposedto the same downhole conditions mentioned above.

Referring to FIG. 3, the perimetrically continuous void 28 extendslongitudinally through the nonswellable member 18. Since walls 42 of thevoid 28 are continuous they have no perimetrical interruptions, such asa longitudinal slit through the nonswellable member 18, for example, andare therefore easily sealed to an outer radial surface 46 of the secondtubular 26. Optionally, a mechanical device 48 can be sealably attachedto both the second tubular 26 and the nonswellable member 18 at bothends where the second tubular 26 exits from the nonswellable member 18thereby preventing any movement between the second tubular 26 and thenonswellable member 18. Additionally, by making the mechanical device 48metal the seal between the second tubular 26 and the mechanical devicecan be a metal-to-metal seal. Embodiments of processes to make theswellable sealing system 10 and particularly the perimetricallycontinuous void 28 will be described below.

Referring to FIG. 4, an embodiment of a process to make the swellablesealing system 10 is illustrated generally at 50. A first nonswellablematerial 54 is wrapped perimetrically around the first tubular 14. Atleast one second tubular 26 is positioned substantially parallel to thefirst tubular 14 and a second nonswellable material 58 is wrapped aroundboth the first tubular 14 and the second tubular 26. Wrapping additionallayers of a third nonswellable material 60 around both the first tubular14 and the second tubular 26 forms a first dam 62A and a second dam 62B.Nylon (not shown) or other material capable of holding the nonswellablematerials 54, 58 and 60 in position while being heated to curingtemperatures is wrapped around all of the nonswellable materials 54, 58and 60. The full assembly is heated to cure the nonswellable materials54, 58 and 60. After curing, the nylon is removed and a swellablematerial 66 is wrapped perimetrically around the nonswellable materials54, 58 between the dams 62A and 62B. Nylon or other material is thenwrapped around the swellable material 66 and the full assembly is againheated, this time to cure the swellable material 66. The nylon isremoved after curing.

Optionally, the step of wrapping the second tubular 26 with thenonswellable material 58, could be replaced with wrapping a rod 70 (orother reusable manufacturing tubular). This may be desirable to avoidoxidation and possible contamination of the passageway 30 of the secondtubular 26 that could occur during manufacture or during the hightemperature curing processes. If the rod 70 were used it would beemployed to form the perimetrically uninterrupted longitudinal void 28in the nonswellable material 58. Doing so, however, would requirewithdrawal of the rod 70 upon completion of the last curing cycle.Application of a release agent, such as, mold release, for example, tothe rod 70 prior to it being wrapped in the nonswellable material 58could facilitate its withdrawal upon completion of the curing process. Astep of inserting the second tubular 26 into the void 28 could be donein conjunction with the withdrawal of the rod 70, by attaching and endof the second tubular 26 to an end of the rod 70. The action ofwithdrawing the rod 70 would then also insert the second tubular 26 intothe void 28.

Referring to FIG. 5, optionally, the nonswellable materials 54, 58, 60could be wrapped only at the dams 62A and 62B. In such case, theswellable material 66 would be wrapped directly over the first tubular14 and the second tubular 26 (or rods 70) between the dams 62A and 62Bas desired by a well operator.

While the invention has been described with reference to an exemplaryembodiment or embodiments, it will be understood by those skilled in theart that various changes may be made and equivalents may be substitutedfor elements thereof without departing from the scope of the invention.In addition, many modifications may be made to adapt a particularsituation or material to the teachings of the invention withoutdeparting from the essential scope thereof. Therefore, it is intendedthat the invention not be limited to the particular embodiment disclosedas the best mode contemplated for carrying out this invention, but thatthe invention will include all embodiments falling within the scope ofthe claims. Also, in the drawings and the description, there have beendisclosed exemplary embodiments of the invention and, although specificterms may have been employed, they are unless otherwise stated used in ageneric and descriptive sense only and not for purposes of limitation,the scope of the invention therefore not being so limited. Moreover, theuse of the terms first, second, etc. do not denote any order orimportance, but rather the terms first, second, etc. are used todistinguish one element from another. Furthermore, the use of the termsa, an, etc. do not denote a limitation of quantity, but rather denotethe presence of at least one of the referenced item.

While one or more embodiments have been shown and described,modifications and substitutions may be made thereto without departingfrom the spirit and scope of the invention. Accordingly, it is to beunderstood that the present invention has been described by way ofillustrations and not limitation.

1. A downhole sealing device, comprising: a swellable member; and apassageway having a perimetrically continuous wall, the swellable memberconfigured to cause sealing between a downhole structure and a pluralityof tubulars in response to being in a swelled condition, the pluralityof tubulars being routed through a plurality of voids extendinglongitudinally through the swellable member, each of the plurality ofvoids having perimetrically continuous walls surrounding each of theplurality of tubulars.
 2. The downhole sealing device of claim 1,wherein the passageway is through one of the plurality of tubulars. 3.The downhole sealing device of claim 1, wherein the swellable member ispolymeric.
 4. The downhole sealing device of claim 1, wherein thepassageway is a control line.
 5. The downhole sealing device of claim 1,wherein the passageway permits passage of at least one selected from agroup consisting of fluid, electrical conductors and fiber optic cable.6. A downhole swellable sealing system with passageway, comprising: atleast one substantially nonswellable member; and a swellable member inoperable communication with the at least one substantially nonswellablemember configured to cause sealing between a downhole structure and aplurality of tubulars in response to being in a swelled condition, theplurality of tubulars being routed through a plurality of voidsextending longitudinally through at least one of the swellable memberand the at least one substantially nonswellable member, each of theplurality of voids having perimetrically continuous walls surroundingeach of the plurality of tubulars.
 7. The downhole swellable sealingsystem with passageway claim 6, wherein one of the at least onesubstantially nonswellable member forms a dam for the swellable member.8. The downhole swellable sealing system with passageway claim 6,wherein the at least one substantially nonswellable member is twosubstantially nonswellable members forming two dams with one dam beinglocated on either longitudinal end of the swellable member.
 9. Thedownhole swellable sealing system with passageway claim 6, wherein theswellable member perimetrically surrounds the at least one substantiallynonswellable member.
 10. The downhole swellable sealing system withpassageway claim 6, wherein at least one of the at least onesubstantially nonswellable member is polymeric.
 11. The downholeswellable sealing system with passageway claim 6, wherein the pluralityof voids extend longitudinally through the at least one substantiallynonswellable member.
 12. The downhole swellable sealing system withpassageway claim 6, wherein the plurality of voids extend longitudinallythrough the swellable member.
 13. A method of making a downholeswellable seal with a passageway therethrough, comprising:perimetrically surrounding a first tubular with a first substantiallynonswellable material; perimetrically surrounding at least one secondtubular with a second substantially nonswellable material; positioningthe at least one second tubular adjacent the first tubular;perimetrically surrounding the first tubular and the at least one secondtubular with a swellable material; curing the first substantiallynonswellable material; curing the second substantially nonswellablematerial; and curing the swellable material.
 14. The method of makingthe downhole swellable seal with a passageway therethrough of claim 13,further comprising: withdrawing the at least one second tubular from thesecond substantially nonswellable material; leaving a void withperimetrically continuous walls in the second substantially nonswellablematerial; and inserting a third tubular into the void.
 15. The method ofmaking the downhole swellable seal with a passageway therethrough ofclaim 14, further comprising connecting the third tubular to the atleast one second tubular prior to withdrawing the at least one secondtubular.
 16. The method of making the downhole swellable seal with apassageway therethrough of claim 13, further comprising sealing thefirst tubular to the first substantially nonswellable material andsealing the at least one second tubular to the second substantiallynonswellable material.
 17. The method of making the downhole swellableseal with a passageway therethrough of claim 13, further comprisingapplying a release agent to the at least one second tubular prior to thesurrounding with substantially nonswellable material.
 18. The method ofmaking the downhole swellable seal with a passageway therethrough ofclaim 13, further comprising damming the swellable material with atleast one of the substantially nonswellable materials.
 19. The method ofmaking the downhole swellable seal with a passageway therethrough ofclaim 18, further comprising sealably attaching a mechanical device tothe at least one second tubular and to the substantially nonswellablematerial that is damming the swellable material.
 20. The method ofmaking the downhole swellable seal with a passageway therethrough ofclaim 19, wherein the sealably attaching of the mechanical device to theat least one second tubular is a metal-to-metal seal.
 21. The method ofmaking the downhole swellable seal with a passageway therethrough ofclaim 19, wherein the sealably attaching includes immobilizing the atleast one second tubular with respect to the substantially nonswellablematerial that is damming the swellable material.
 22. The method ofmaking the downhole swellable seal with a passageway therethrough ofclaim 13, further comprising perimetrically surrounding at least one ofthe first substantially nonswellable material and the secondsubstantially nonswellable material with the swellable material.